(21.4–26.4) |
474.3 (±251.7) |
1 | 0.418 |
| 2 | 0.920 | 3 0.525 |
0.154 |
HBI |
5.7 (±4.0) |
7.9 (±3.1) |
History of surgery |
Yes (n = 19) No (n = 58) |
455.8 (±270.9) 504.3 (±236.4) | 1.5 (IQR:0.0–3.0) |
N.A |
1 N.A 2 <0.001 3 N.A |
0.457 |
PMS |
2.5 (IQR:1.0–4.0) |
3.9 (±1.7) |
Other chronic diseases |
Yes (n = 23) No (n = 53) | 0.8 | (IQR:0.0–1.0) |
N.A |
514.0 (±258.4) 483.1 (±240.0)1 N.A 2 |
0.615 <0.001 3 N.A |
N smoking (%) |
21 (27.3) |
13 (27.1) |
8 (27.6) |
8 (19.0) |
1 0.318 2 0.962 3 0.369 |
N Steroids (%) |
25 (32.5) |
25 (52.1) |
0 (0.0) |
N.A |
N.A |
N Azathioprine (%) |
27 (35.1) |
14 (29.2) |
13 (44.8) |
N.A |
1 N.A 2 0.163 3 N.A |
N with other chronic diseases (%) |
23 (29.9) |
16 (33.3) |
7 (24.1) |
N.A |
1 N.A 2 0.393 3 N.A |
Chemerin (ng/mL) |
492.3 (±244.3) |
559.1 (±235.6) |
381.7 (±220.2) |
404.5 (±194.2) |
1 0.047 2 0.002 3 0.001 |
Chemerin/BMI (ng·m2/mL·kg) |
21.4 (±11.0) |
24.2 (±10.6) |
16.7 (±10.1) |
17.6 (±9.1) |
1 0.057 2 0.003 3 0.002 |
The patients had the following inflammatory lesion localizations: 53 in the colon (68.8%), 11 in the ileum and colon (14.6%), and 4 in the ileum (10.3%); 3 patients had erosions or ulcers detected at gastroscopy as well as inflammation, erosions or ulcers in the small intestines (3.8%), and 2 had no data (2.5%). No statistical difference was observed between serum chemerin levels based on inflammatory changes location (
p > 0.05).
Overall, IBD patients had significantly higher chemerin levels than HCs (
p = 0.047). Among them, only patients with active disease had significantly higher serum levels of chemerin than HCs (
p = 0.001), which was not observed in patients in remission. Moreover, patients with IBD exacerbation had significantly higher chemerin levels compared to patients in remission (
p = 0.002,
Table 1).
Serum chemerin levels were significantly higher in UC patients (557.4 ± 219.9 ng/mL) compared to CD (446.0 ± 252.6 ng/mL;
p = 0.048). Mean chemerin levels were significantly higher in UC patients compared to controls (557.4 ± 219.9 ng/mL vs. 404.5 ± 194.2 ng/mL;
p = 0.002) and not different in CD patients and controls (446.0 ± 252.6 ng/mL vs. 404.5 ± 194.2 ng/mL;
p = 0.395). Patients with CD exacerbation had significantly higher chemerin levels than those with CD remission (528.1 ± 235.5 ng/mL,
n = 29 vs., 297.3 ± 216.8 ng/mL;
n = 16,
p = 0.002). Mean chemerin levels were not different between UC exacerbation and remission group (606.5 ± 234.0 ng/mL,
n = 19 vs., 485.5 ± 182.4 ng/mL,
n = 13;
p = 0.128).
Chemerin levels correlated with the clinical severity of CD as assessed by HBI (r = 0.478,
p = 0.001;
Figure 1), but not with the severity of UC by PMS scale (r = 0.035,
p = 0.851). Besides this, among all IBD patients, no correlation was seen between chemerin levels and BMI (r = 0.030,
p = 0.788).
Figure 1. The correlation between chemerin concentration and the Harvey–Bradshaw index results (r = 0.478, p = 0.001) in CD patients. HBI: Harvey–Bradshaw index.
As many studies noted a correlation between BMI and chemerin, we have created a new parameter: chemerin/BMI (ng·m
2/mL·kg). This parameter was higher in IBD patients with exacerbation than in remission (
p = 0.003;
Table 1).
Furthermore, serum chemerin levels significantly decreased after 14 weeks of biological treatment (519.6, IQR: 393.2–727.0 ng/mL vs. 351.5, IQR: 229.3–424.2 ng/mL;
p = 0.002;
Figure 2).
Figure 2. The serum level of chemerin in patients before and after anti-TNF therapy. Solid line: decreased concentration; dashed line: increased concentration.
After anti-TNF therapy, 20 patients achieved clinical remission, while 6 patients still had active disease. There was no difference in the chemerin levels measured before treatment in these patient subgroups (532.2 ± 166.0 mg/mL vs. 512.7 ± 398.4 ng/mL;
p = 0.860). However, after treatment, patients in remission had significantly lower levels of chemerin than patients with exacerbation (319.8 ± 118.7 ng/mL vs. 599.7 ± 318.9 ng/mL;
p = 0.003). Additionally, the ratio of serum levels of chemerin measured before and after anti-TNF treatment was higher in patients, who reached remission after 14 weeks of therapy compared to the group in which the disease was still active (1.53 IQR: 1.19–2.09,
n = 20 vs. 0.80 IQR: 0.60–0.97,
n = 6;
p < 0.001).
No effect of other accompanying chronic diseases, treatment with immunomodulators, or history of abdominal surgery on chemerin levels was observed. Patients treated with anti-TNF before therapy had similar levels of chemerin compared to the remaining IBD group. However, patients treated with steroids revealed higher concentrations of chemerin compared to patients who did not receive this treatment (
p = 0.049,
Table 2).
Table 2. Relationship between the selected clinical parameters and the concentration of chemerin in the IBD patients’ blood serum.
Parameters |
Chemerin (ng/mL) |
p |
Steroids * |
Yes (n = 25) No (n = 52) |
624.0 (IQR: 362.4–793.6) 454.0 (IQR: 288.3–598.9) |
0.049 |
Azathioprine * |
Yes (n = 27) No (n = 50) |
445.7 (IQR: 264.7–613.5) 490.6 (IQR: 303.0–742.5) |
0.265 |
Anti-TNF ** |
Yes (n = 26)
|
Fistulas in CD |
Yes ( | n = 7) No (n = 38) |
615.5 (±267.4) 414.8 (±240.5) |
0.052 |
Smoking |
Yes (n = 13) No (n = 64) |
529.3 (±214.3) 484.8 (±250.8) |
0.553 |
3. Conclusions
In conclusion, chemerin positively correlated with the clinical severity of IBD, and its level decreased after anti-TNF treatment. As shown in the present study, as well as in others, chemerin may be an indicator of clinical activity of IBD—CD in particular—as well as being useful in anti-TNF treatment monitoring. It would be useful to further compare the clinical value of chemerin with other known markers of IBD severity—in particular, with calprotectin. Additionally, future research should focus on the molecular basis of the relationship between chemerin levels and responses to anti-TNF therapy.